Two approaches to aiding longterm heavy cigarette smokers to permanently cease smoking, derived from clinical research reported by MRFIT, Stanford Heart Disease Prevention Project, and UCLA Center for Health Enhancement, will be experimentally evaluated at representative worksites. A Health Lifestyle mode will integrate smoking-related training in exercise, weight management, and stress management with cognitive-behavioral smoking cessation methods. A Social Support mode will integrate assertion training, family therapy, and organizational development methods with the cognitive-behavioral foundation. The third experimental condition will be a state-of-the-art Cognitive-Behavioral smoking cessation intervention. Intervention will be conducted in 6-8 participant groups by 4 experienced and specially trained smoking specialists, extending over 8 weeks in an initial phase and followed by up to 3 years of Extended Intervention tailored to each intervention mode and to the needs and smoking status of participants. Two hundred eighty eight employees (ages 25-60 and low-level white collar, approximately equal male-female) at 3 worksites will be randomly assigned to experimental conditions, and within each condition to one of the 4 specialists and one of two initial schedules (weekly for 8 weeks vs. daily for 5 days with 3 further sessions over 7 weeks). Self-report and saliva thiocyanate measures of smoking will be assessed at pretest, postest, monthly followups for 12 months, and yearly followups for up to 3 years. Smoking motivations and styles, stress coping style (Type A behavior), exercise pattern, weight, and social support network will also be assessed at pretest and followup periods to predict and evaluate intervention outcomes.